Add stripHexPrefix method in web3 utils with tests

[ashwinYardi]

Description

Added stripHexPrefix method in web3.utils

Fixes #3776

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist:

• I have selected the correct base branch.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• Any dependent changes have been merged and published in downstream modules.
• I ran npm run dtslint with success and extended the tests and types if necessary.
• I ran npm run test:unit with success.
• I ran npm run test:cov and my test cases cover all the lines and branches of the added code.
• I ran npm run build and tested dist/web3.min.js in a browser.
• I have tested my code on the live network.
• I have checked the Deploy Preview and it looks correct.
• I have updated the CHANGELOG.md file in the root folder.

[coveralls]

Coverage increased (+2.4%) to 80.433% when pulling 0d256cf on ashwinYardi:fix/web3-util-stripHexPrefix into edf481d on ethereum:1.x.

[GregTheGreek]

Please do not commit the build directories under ./dir

[GregTheGreek]

see above comment

[spacesailor24]

Closing this in favor of #3781 because it adds more tests, corrects the regex, and follows preexisting package patterns